Seal assembly

ABSTRACT

A seal assembly includes a connector body having an open end configured for receiving a free end of a pipe and an adaptor for securing at the free end of the pipe. The adaptor has a first ring, configured to be mounted around the circumference of the free end of a pipe, and a second ring configured to cooperate with the first ring in order to drive the first ring into engagement with an outer surface of the pipe. A mechanical interlock arrangement is configured for driving the adaptor in the direction of the connector body, when the adaptor is secured at the free end of the pipe. The mechanical interlock arrangement is further configured for preventing or limiting axial movement of the pipe relative to the connector body, when the adaptor is secured to the outer surface of the pipe and when the free end of the pipe is in sealing contact with a metal seal surface of the connector body.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/338,018, filed Mar. 29, 2019, pending, which is the U.S. nationalphase of International Application No. PCT/GB2017/053088 filed Oct. 12,2017 which designated the U.S. and claims priority to Great BritainPatent Application No. 1617299.1 filed Oct. 12, 2016, the entirecontents of each of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a seal assembly, more particularly, butnot exclusively, to a seal assembly for a metal-to-metal seal to becreated between a connector and a pipe.

BACKGROUND OF THE INVENTION

There is an ongoing requirement within the oil industry to providecost-efficient and consistent methods of connecting oil pipes togetherin a way that minimises the risk of oil leakage.

Typically, flanged joints are used. These have a number ofdisadvantages. For example, flanged joints are vulnerable and can becompromised by uneven bolt tightening. Moreover, rubber seals aregenerally used within these joints, and often fail due to thermaldegradation, as well as being at significant risk of damage andsubsequent failure from bad practice when joints are assembled on site.

Flanged joints also require welding. This is time consuming duringassembly, increasing down time for pipe repairs as well as presenting afire risk. Further, amidst recent proposals for better offshore pipelineregulation and more refined safety rules covering repairs, there is arequirement to employ qualified welders to perform any repairs, which isa considerable added expense. The installation of flange joints alsorequires very high precision, requiring highly skilled labour forassembly, further increasing the cost of installation, repair andmaintenance.

The present invention seeks to overcome or at least mitigate/alleviateone or more problems associated with the prior art.

SUMMARY OF THE INVENTION

A first aspect of the invention provides a seal assembly. The sealassembly comprises a connector body having an open end configured forreceiving a free end of a pipe. An adaptor is provided for securingadjacent the free end of the pipe (e.g. to an outer surface of the pipe,at a location adjacent the free end of the pipe). A mechanical interlockarrangement is provided, wherein the mechanical interlock is configuredfor driving the adaptor in the direction of the connector body, e.g.when the adaptor is secured to the outer surface of the pipe. Theconnector body includes a seal surface, and the mechanical interlock isconfigured for driving the free end of the pipe against the seal surfaceof the body, e.g. when the adaptor is secured to the outer surface ofthe pipe, in order to create a seal between the free end of the pipe andsaid seal surface of the connector body. The mechanical interlockarrangement is further configured for preventing or limiting axialmovement of the pipe relative to the connector body, when the free endof the pipe is in sealing contact with said seal surface of theconnector body.

In exemplary embodiments, the free end of the pipe comprised a metalsurface and said seal surface of the connector body comprises a metalsurface, such that a metal-to-metal seal is created between the free endof the pipe and the connector body.

The configuration of the seal assembly allows for the creation of a sealwith a pipe without the requirement for traditional pipe flanges. Itfollows that no welding step is required, which advantageously reducesthe risk of fires occurring and removes the need to employ qualifiedwelders. The seal assembly allows a reliable, high-qualitymetal-to-metal seal is established between the connector body and thepipe. This advantageously removes the requirement for rubber seals,which are susceptible to thermal degradation and mechanical damage inuse.

The configuration of the seal assembly also allows for a pipe andconnector body to be connected in sealing engagement quickly and easily.Should separation of the pipe and connector body be required, forexample to allow the apparatus to be cleaned or moved, or thereplacement of worn or damaged components, the assembly can be quicklyand easily detached. This would not be possible if a flanged connectionwere utilised. These features are distinctly advantageous should theassembly be utilised within the oil and gas industry, wherein rapidset-up and removal of drilling and oil and gas transport equipment canoffer savings in both time and money to an operator, which is ofdistinct commercial advantage.

In exemplary embodiments, the metal-to-metal seal is established throughthe straightforward movement of the adaptor towards the connector body.As a result, the assembly can advantageously be quickly and easilyconnected to a pipe, to rapidly establish a reliable seal therebetweenwithout the need for supplementary components, further demandingprocessing steps such as welding or complex tooling.

In exemplary embodiments, the connector body comprises a bore, andwherein the seal surface is part of a side wall of the bore. Such aconfiguration permits the creation of a seal with a specifically definedpoint on the outer surface of the free end of each pipe (e.g. an outersurface or an axial end surface at the very end of the pipe). Moreover,the seal is self-creating upon the free end of a pipe being drivenagainst the seal surface of the connector body, meaning that,advantageously, a reliable and high-quality seal is quickly achievable.

In exemplary embodiments, the bore of the connector body defines a fluidflow path for fluid travelling from the pipe into the connector body. Inexemplary embodiments, the seal surface extends from the open end of theconnector body to a location within the connector body, so that a sealcan be created adjacent the open end of the connector body.

In exemplary embodiments, the diameter of the bore decreases away fromthe open end of the connector body. Providing a bore of progressivelydecreasing diameter advantageously ensures that the metal-to-metal sealis created as the free end of a pipe is inserted within the open end ofthe connector body, and then simply moved in the direction of theconnector body.

In exemplary embodiments, the bore has a central longitudinal axis andis defined by a circumferential side wall, and wherein a portion of theside wall extends away from the open end of the connector body at anangle of less than 10° with respect to the central longitudinal axis.

In exemplary embodiments, the portion of the side wall extends at anangle of substantially 4° with respect to the central longitudinal axis.

It has been found that tapering a portion of the side wall of the boreof the connector body at an angle of less than 10° with respect to thecentral longitudinal axis, advantageously allows a metal-to-metal sealto be created between the free end of a pipe and the side wall of thebore of the connector, as the free end of the pipe is inserted withinthe free end of the connector body, without unduly limiting the volumeof the bore available for the transmission of a fluid through theconnector body.

In exemplary embodiments, the adaptor comprises a first ring, configuredto be mounted around the circumference of the free end of a pipe, and asecond ring configured to cooperate with the first ring in order todrive the first ring into engagement with an outer surface of the pipewhen the adaptor is driven in the direction of the connector body by themechanical interlock arrangement.

In exemplary embodiments, the first ring has an angled outer surfacedefining a first taper, and the second ring has an angled inner surfacedefining a second taper complimentary to said first taper, whereincontact forces acting therebetween increase upon axial movement of thesecond ring relative to the first ring in the direction towards theconnector body, for driving the first ring in a radial direction intocontact with the outer surface of a pipe.

Advantageously, the first ring and the second ring are configured suchthat straightforward relative movement therebetween, as a result of thesecond ring being moved in the direction of the connector body issufficient to secure the first ring with respect to the outer surface ofa pipe, and to create a metal-to-metal seal between the connector bodyand the free end of the pipe. As a result, such a configuration mayprovide an operator with savings in both time and money when setting up,and dismantling the sealing assembly.

In exemplary embodiments, the first ring has a first end, a second endand a central longitudinal axis, and wherein the angled outer surfaceextends between the first and second ends at an angle of between 5 and15° with respect to the central longitudinal axis.

In exemplary embodiments, the angled outer surface extends at an angleof substantially 8° to the central longitudinal axis.

It has been found that tapering the angled outer surface of the firstring at an angle of between 5° and 15° with respect to the centrallongitudinal axis, advantageously allows a minimum level of relativemovement between the first ring and the second ring to result in amaximum increase in contact stresses acting therebetween.Advantageously, this means an operator only has to move the second ringa small distance, in order to achieve ensure that the first ring issecurely attached to the outer surface of a pipe.

In exemplary embodiments, the first end of the first ring comprises afirst radial stop surface, arranged for abutment by the second ring, tolimit movement of the second ring in the direction towards the connectorbody.

The provision of such a radial stop limits the extent to which thesecond ring may be moved relative to the first ring, in the directiontowards the connector body. Advantageously, this ensures that the secondring is prevented from overriding the first ring when the seal assemblyis connected to the free end of a pipe, thus reducing the likelihood ofdamage to the assembly and the metal-to-metal seal being compromised.

In exemplary embodiments, the connector body includes a first recess,and wherein the first end of the first ring is configured to nest withinsaid recess when the second ring is driven in the direction of theconnector body.

The dimensions of the first end of the first ring and the recess areconfigured such that the first end of the first ring may nest within therecess. This ensures that the concentricity of the first ring, thesecond ring, the connector body and an inserted pipe is maintained.Advantageously, this ensures that a reliable seal is maintained betweenthe connector body and the inserted pipe even when the pipe may besubject to externally acting forces, such as a bending moment.

In exemplary embodiments, the first end of the first ring comprises atapered outer surface configured to cooperate with a side wall of thefirst recess, to assist the passage of the first end of the first ringinto the first recess.

In exemplary embodiments, the first recess is configured to be arrangedadjacent the outer surface of a pipe, when said pipe is inserted intothe open end of the connector body.

In exemplary embodiments, the connector body has a substantiallycylindrical form defined by a circumferential side wall, wherein saidside wall has an end face having a stepped profile which defines thefirst recess, and wherein an innermost wall of the first recess isadjacent the bore of the connector body.

It has been found that the point at which the first ring engages withthe connector body, when the adaptor is secured with respect to theconnector body, may act as a pivot point when externally acting forces,such as bending moments, act on a connected pipe. It has also been foundthat minimising the radial distance of this point from the pipe cangreatly reduce the impact of said external forces on the integrity ofthe metal-to-metal seal between the free end of the pipe and theconnector body. As a result, the likelihood of fluid leakage is greatlyreduced.

In exemplary embodiments, the first recess comprises an opening, andwherein the width of the opening is less than 50% of the radial width ofthe circumferential side wall.

In exemplary embodiments, the width of the opening is substantially 30%of the radial width of the circumferential side wall.

The dimensions of the recess are configured such that the point at whichan attached pipe may pivot with respect to the connector body, shouldexternal forces such as bending moments act on said pipe, is located asclosely to the pipe as possible. Advantageously, this greatly reducesthe likelihood that the metal-to-metal seal between the connector bodyand the attached pipe will be compromised as a result of said forces,and that fluid leakage may result. In addition, such dimensions allowfor the radial width of the connector body to be maximised, i.e.formation of the recess does not require the removal of material to anextent that may compromise the structural or mechanical integrity of theconnector body.

In exemplary embodiments, the innermost wall of the first recess definesa radial stop surface arranged to engage a second radial stop surfaceprovided on the first end of the first ring, and wherein abutment of thesecond radial stop surface with the innermost wall of the first recessprevents further movement of the adaptor in the direction towards theconnector body.

The provision of such a radial stop limits the extent to which the firstring may move towards the connector body, and as such advantageouslyprovides for continued movement of the second ring towards the connectorbody when the stop surfaces are in abutment to serve to increase thesecurity of engagement between the first ring and the pipe.

In exemplary embodiments, an inner surface of the first ring isnon-planar, and is configured to securely engage with the outer surfaceof a pipe.

The inner surface of the first ring is configured such that uponengagement with the outer surface of a pipe, and upon movement of thesecond ring with respect to the first ring in the direction towards theconnector body, the first ring may securely grip the outer surface ofthe pipe. As a result, the likelihood of undesired relative movementbetween the first ring and the pipe is advantageously reduced, and thefree end of a pipe may be more reliably driven into the open end of theconnector body upon further movement of the second ring with respect tothe first ring, to create a metal-to-metal seal between the free end ofthe pipe and the connector body.

In exemplary embodiments, the non-planar profile of the inner surface ofthe first ring is configured to engage the outer surface of a pipe byvirtue of an interference fit.

Configuring the inner surface of the first ring such that engagementwith the outer surface of a pipe is by virtue of an interference fit,provides an advantageously low-complexity arrangement wherein no furthersupplementary components are required to ensure a secure engagementbetween the first ring and a pipe.

In exemplary embodiments, the first ring includes a keying surfaceconfigured for purchase into the outer surface of a pipe.

Advantageously, such an arrangement means that no modification of theouter surface of the pipe is required to ensure that the first ring maysecurely engage with the outer surface of a pipe.

In exemplary embodiments, the inner surface of the first ring comprisesa profile configured to complement a non-planar profile of the outersurface of a pipe.

In exemplary embodiments, the inner surface of the first ring comprisesa plurality of projections (e.g. teeth or barbs), configured to bereceived in a series of recesses on the outer surface of a pipe.

By providing the inner surface of the first ring with a profile, such asa series of projections, that complements the profile of the outersurface of a pipe (i.e. a series of recesses), the first ring may engagemore securely with the outer surface of said pipe.

Advantageously, this provides for the pipe being driven more reliablyinto the open end of the connector body, which in turn provides for areliable, high quality metal-to-metal seal being created between thepipe and connector body.

In exemplary embodiments, the assembly further comprises a locatingarrangement for ensuring a desired alignment of the mechanical interlockarrangement with the connector body, as the adaptor is moved in thedirection towards the connector body.

The provision of a locating arrangement further ensures that theconcentricity of the first ring, the second ring, the connector body andeach inserted pipe is maintained. Advantageously, this ensures that areliable seal is maintained between the connector body and the insertedpipe even when the pipe may be subject to externally acting forces, suchas a bending moment.

In exemplary embodiments, the locating arrangement comprises an end faceof the connector body having a second recess, and an end face of theadaptor having a projection configured to be received within said recessduring movement of the adaptor in the direction towards the connectorbody.

Such an arrangement requires no additional, supplementary components tomaintain the position of the adaptor with respect to the connector body.The apparatus is therefore of advantageously low-complexity, meaningthat the process of manufacturing the seal assembly can be simplified,and the likelihood that components of the assembly will be dropped andpotentially lost during attachment and detachment of the assembly isalso reduced.

In exemplary embodiments, the locating arrangement comprises the endface of the connector body having a plurality of recesses, and the endface of the adaptor having a plurality of projections configured to bereceived within said recesses.

The provision of a plurality of recesses and a plurality of projectionsensures that the concentricity of the first ring, the second ring, theconnector body and the inserted pipe is maintained as accurately aspossible. Advantageously, this further ensures that a reliablemetal-to-metal seal is maintained between the connector body and theinserted pipe even when the pipe may be subject to externally actingforces, such as a bending moment.

In exemplary embodiments, the projections comprise a series ofcastellations, wherein said castellations project at regular intervalsaround the circumference of the end face of the adaptor, preferablywherein said castellations are arcuate.

Advantageously, distributing the projections at regular intervals aroundthe circumference of the end face of the second ring ensures that shouldan external force, such as a bending moment, act on a pipe inserted intothe connector body, the load is more evenly distributed around theinterface between the second ring and the connector body. The evendistribution of said force therefore greatly reduces the likelihood thatthe concentricity of the first ring, the second ring, the connector bodyand the inserted pipe relative to one another will be lost, and as such,greatly reduces any negative impact on the integrity of themetal-to-metal seal between the connector body and the free end of thepipe.

In addition, it has been found that by providing said castellations,such a configuration further distributes said externally acting forcemore evenly across each projection. Advantageously, the likelihood thatany one projection may fail and break away from the second ring underthe action of such a force, is greatly reduced.

In exemplary embodiments, the mechanical interlock arrangement comprisesa fastening arrangement for pulling the connector body in the directionof the adaptor, in order to drive the internal surface of the connectorbody into sealing engagement with the free end of the pipe and to drivethe free end of a pipe into the open end of the connector body.

The provision of a fastening arrangement means that the adaptor can besecured in place with respect to the connector body, when the secondring is moved fully in the direction of the connector body. Therefore,advantageously, the metal-to-metal seal between the free end of the pipeand the connector body can be easily and reliably maintained oncecreated, with relative movement between each connected pipe and theconnector body minimised.

In exemplary embodiments, the fastening arrangement comprises theadaptor having a plurality of fasteners, and the connector body having aplurality of fastening points configured to receive said fasteners, andwherein the fastening arrangement is configured to releasably attach theadaptor to the connector body.

By providing the second ring with a plurality of fasteners, and theconnector body with a plurality of fastening points configured toreceive said fasteners, the second ring can be advantageously quicklyand easily attached to the connector body upon the adaptor having beenmoved fully in the direction of the connector body, such that ametal-to-metal seal exists between the connector body and the free endof an inserted pipe. In addition, the second ring can be quickly andeasily detached from the connector body by virtue of said attachmentbeing releasable, should an operator wish to remove the seal assembly.

In exemplary embodiments, the adaptor has a plurality of aperturesextending therethrough, and wherein the fasteners are configured to beinserted through said apertures in the direction towards the connectorbody.

In exemplary embodiments, the fastening points comprises a plurality ofrecesses, configured to align with the fasteners and to releasablyattach to said fasteners during movement of the adaptor in the directiontowards the connector body.

In exemplary embodiments, the fasteners are bolts, and wherein thefastening points are threaded holes having a corresponding thread tothat of each bolt.

Advantageously, a low-complexity arrangement is provided for attachingthe second ring to the connector body. Such low-complexity ensures thatthe seal assembly can be quickly and easily attached, and secured by anoperator in a potentially time-critical situation, without therequirement for complex tooling. Further, the costs associated withmanufacturing the fastening arrangement, and as such the seal assemblyas a whole, can be reduced.

In exemplary embodiments, the fasteners are arranged at regularintervals around the circumference of the adaptor, and wherein thefastening points are located at regular intervals around the end face ofthe connector body, and wherein the position of each fastener iscomplementary to the position of each fastening point.

Advantageously, distributing the fasteners at regular intervals aroundthe circumference of the end face of the second ring ensures that shouldan external force, such as a bending moment, act on a pipe inserted intothe connector body, the load is more evenly distributed around theinterface between the second ring and the connector body. The evendistribution of said force therefore greatly reduces the likelihood thatthe second ring may become detached from the connector body, or thatconcentricity of the first ring, the second ring, the connector body andthe inserted pipe relative to one another will be detrimentallyaffected. Such a configuration therefore greatly reduces any negativeimpact of such an external force on the integrity of the metal-to-metalseal between the connector body and the free end of each pipe.

In exemplary embodiments, the position of each fastener alternates withthe position of each castellation around the circumference of theadaptor.

Advantageously, distributing the fasteners and projections at regular,alternating intervals around the circumference of the end face of thesecond ring maximises the stability of the interface between the secondring and the connector body, and optimises the distribution of loadshould an external force, such as a bending moment, act on a pipeinserted into the connector body.

In exemplary embodiments, the connector body comprises substantiallyidentical first and second open ends configured for receiving the freeends of first and second pipes, respectively, and wherein the sealassembly further comprises; first and second adaptors, one for securingaround the free end of a respective one of said first and second pipes;

and first and second mechanical interlock arrangements, configured fordriving a respective one of each of said first and second adaptors inthe direction of the connector body to create a metal-to-metal sealbetween each of said first and second pipes and the connector body, andconfigured for preventing or limiting axial movement of each of saidfirst and second pipes relative to the connector body.

The configuration of the seal assembly allows two pipes to be connectedin sealing engagement, without the requirement for traditional pipeflanges. It follows that no welding step is required, whichadvantageously reduces the risk of fires occurring and removes the needto employ qualified welders. The seal assembly allows a reliable,high-quality metal-to-metal seal is established between the connectorbody and each pipe. This advantageously removes the requirement forrubber seals, which are susceptible to thermal degradation andmechanical damage in use.

The configuration of the seal assembly also allows for two pipes to beconnected in sealing engagement quickly and easily. Should separation ofthe pipes and connector body be required, for example to allow theapparatus to be cleaned or moved, or the replacement of worn or damagedcomponents, the assembly can be quickly and easily detached. This wouldnot be possible if a flanged connection were utilised. These featuresare distinctly advantageous should the assembly be utilised within theoil and gas industry, wherein rapid set-up and removal of drilling andoil and gas transport equipment can offer savings in both time and moneyto an operator, which is of distinct commercial advantage.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described with reference to theaccompanying drawings, in which:

FIG. 1 is a perspective view of a seal assembly according to anembodiment of the invention.

FIG. 2 is a cross sectional view of the seal assembly of FIG. 1 ,wherein the seal assembly is shown in an unsecured condition.

FIG. 3 is a cross sectional view of the seal assembly of FIG. 1 ,wherein the seal assembly is shown in a secured condition.

DETAILED DESCRIPTION OF EMBODIMENT(S)

Referring firstly to FIG. 1 , a seal assembly for a pipe is indicatedgenerally at 100.

The seal assembly includes; a connector body 102, an adaptor 115 and amechanical interlock arrangement 104. The mechanical interlockarrangement 104 is configured for cooperation between the adaptor 115and the connector body 102 such that the adaptor 115 may be driven inthe direction of the connector body 102, to create a metal-to-metal sealbetween a pipe 106 and the connector body 102.

The mechanical interlock arrangement 104 is also configured for securingthe adaptor 115 with respect to the connector body 102 to prevent orsubstantially limiting axial movement of the connector body 102 relativeto the free end of the pipe 106, once said pipe 106 has been insertedinto the connector body 102. To allow this, the mechanical interlockarrangement 104 is movable between an unsecured condition (illustratedin FIG. 2 ), in which the pipe 106 has been inserted into the connectorbody 102 but may still be easily removed, and a secured condition(illustrated in FIG. 3 ), in which the position of the pipe 106 issecurely fixed with respect to the connector body 102, and cannot beremoved without the mechanical interlock arrangement 104 being movedback into the unsecured condition.

Referring now to FIG. 2 , wherein the seal assembly 100 is shown in anunsecured condition, the connector body 102 has a substantiallycylindrical form, having first and second ends 108, 110 which aresubstantially identical, mirror images of one another. Each of the firstand second ends 108, 110 of the connector body 102 has an opening 112,each of which are configured to receive the free end 114 of a pipe 106.Each of the first and second ends 108, 110 of the connector body 102 isconfigured to engage with a substantially identical adaptor 115 andmechanical interlock arrangement 104. For reasons of conciseness, theseal assembly 100 will now be described further with reference to asingle adaptor 115 and mechanical interlock arrangement, which may belocated at either the first 108 or second 110 end of the connector body102.

In the described embodiment, the adaptor 115 includes a first ring, 116,and a second ring 118. The first ring 116 is configured to be mountedaround the circumference of the free end of a pipe 106, and defines anaperture with a diameter closely matched to the outer diameter of thedesired pipe to be coupled. In the described embodiment, the first ring116 is a split ring. The provision of a split ring ensures that the pipe106 may be initially inserted into the aperture, but that once inserted,the first ring 116 will be engaged in close contact with the outersurface 120 of the pipe 106.

An inner surface 120 of the first 116 ring is non-planar, and isconfigured to securely engage with the outer surface of a pipe 106. Thisconfiguration allows the first ring 116 to securely grip the outersurface of the pipe 106 and as a result, the likelihood of undesiredrelative movement between the first ring 116 and the pipe 106 isadvantageously reduced. In the described embodiment, the non-planarprofile of the inner surface 120 of the first ring 116 includes a seriesof circumferential ridges 122, configured to engage with correspondingchannels 124 formed around the outer circumference of the outer surfaceof the pipe 106 by virtue of an interference fit. In alternativeembodiments, the inner surface 120 of the first ring 116 and the outersurface of the pipe may have alternative, complementary profiles, or theinner surface 120 of the first ring 116 may include a keying surfaceconfigured for purchase into the outer surface of the pipe 106.

Referring again to FIG. 2 , the first ring 116 has a first end 126 and asecond end 128, with an angled outer surface 130 extending therebetween.The angled outer surface 130 is configured to slidably engage with anangled inner surface 132 that extends between a first end 134 and asecond end 136 of the second ring 118. The first ring 116 and the secondring 118 share a central longitudinal axis, indicated by X-X in FIGS. 2and 3 .

The angled outer surface 130 of the first ring 116, and the angled innersurface 132 of the second ring 118 each extend at an angle ofsubstantially 8° with respect to the central longitudinal axis. When thesecond ring 118 is moved relative to the first ring 116 such that theangled inner surface 132 the second ring 118 slides over the angledouter surface 130 of the first ring 116, contact stresses arisingtherebetween increase greatly, which acts to drive the first ring 116into engagement with the outer surface of the pipe 106.

Tapering the angled outer surface 130 of the first ring 116 and theangled inner surface 132 of the second ring 118 at an angle ofsubstantially 8° with respect to the central longitudinal axis,advantageously allows a minimum level of relative movement between thefirst ring 116 and the second ring 118 to result in a maximum increasein contact stresses acting therebetween. Advantageously, this means anoperator only has to move the second ring 118 a small distance in orderto ensure that the first ring 116 is securely attached to the outersurface of the pipe 106. In alternative embodiments, the angled outersurface may extend at an angle of between 5° and 15° with respect to thecentral longitudinal axis.

The first end 126 of the first ring 116 has a collar 138, an outwardlyfacing surface 140 of which defines the maximum diameter of the firstring 116. The collar 138 has a first radial stop surface 142, arrangedto substantially face the first end 134 of the second ring 118. Theradial stop surface 142 is configured to abut the first end 134 of thesecond ring 118, and therefore limit the maximum extent to which thesecond ring 118 can be moved relative to the first ring 116 in adirection towards the connector body 102, and into the secured position.

The first ring 116 and the second ring 118 are therefore configured tocooperate when the second ring 118 is moved relative to the first ring116 in the direction of the connector body 102, such that the first ring116 is driven into engagement with the outer surface of the pipe 106,whilst at the same time, the radial stop surface 142 prevents the secondring 118 from overriding the first ring when the seal assembly 100 isconnected to the free end 114 of a pipe 106, thus reducing thelikelihood of damage to the seal assembly 100 and the metal-to-metalseal being compromised. In addition, this configuration prevents thesecond ring from overriding the first ring when the sealing assembly isattached to a first and a second pipes in fluid communication, and saidfirst and second pipes are subject to external stresses such as bendingmoments, which helps to ensure the structural integrity of theconnection and in turn maintain the integrity of the metal-to-metalseal.

The adaptor 115 is configured such that as the second ring 118 is movedtowards the connector body 102, whilst the angled outer surface 130 ofthe first ring 116 is in contact with the angled inner surface 132 ofthe second ring 118, the free end of the pipe 106 is driven into theopening 112 of the connector body 102. This allows a metal-to-metal sealto be created between the pipe 106 and the connector body 102 throughstraightforward relative motion between components of the adaptor 115.As a result, the assembly can advantageously be quickly and easilyconnected between two pipes, to rapidly establish a reliable sealtherebetween without the need for supplementary components, furtherdemanding processing steps such as welding or complex tooling.

The connector body 102 comprises a bore 144 defined by a circumferentialside wall 146, extending between the opening 112 at the first end 108 ofthe connector body 102 and the opening 112 at the second end 110 of theconnector body 102. The bore 144 has a central longitudinal axis that issubstantially coaxial with the central longitudinal axes of the firstring 116 and the second ring 118, and is also indicated by X-X in FIGS.2 and 3 . The diameter of the bore 144 decreases as the side wall 146extends between the opening 112 and a mid-point of the connector body102 (i.e. the diameter of the bore 144 has a maximum value at eachopening 112, and a minimum value at the mid-point of the connector body102). This configuration means that when the pipe 106 is driven into theconnector body by as a result of the second ring 118 being moved in thedirection of the connector body 102 whilst in contact with the firstring 116, the free end 114 of the pipe 106 is driven into contact withthe side wall 146 of the bore 144. More specifically, the outer surface148 of the free end 114 of the pipe 106 is driven into contact with theside wall 146 of the bore 144. This results in local deformation of thesurface 148 of the pipe 106, which in turn forms a metal-to-metal sealbetween the outer surface 148 of the free end 114 of the pipe 106 andthe side wall 146 of the bore 144. The metal-to-metal seal is thereforeself-creating upon the free end 114 of the pipe 106 being inserted intothe free end of the connector body 102, meaning that advantageously, areliable and high-quality seal is quickly achievable.

Referring now to FIG. 3 , in which the seal assembly 100 is shown in asecured condition, in the described embodiment, the minimum diameter ofthe bore 144 is larger than the diameter of the lumen of each insertedpipe 106. This configuration ensures that there is minimal restrictionon the passage of a fluid through the connector body 102. In alternativeembodiments, the minimum diameter of the bore 144 may be substantiallyequal to the diameter of the lumen of each inserted pipe 106. In yetfurther alternative embodiments, the minimum diameter of the bore 144may be smaller than the diameter of the lumen of each inserted pipe 106.

The metal-to-metal seal is created close to the flow path of fluidthrough the connector body 102, between the free ends 114 of each pipe106. Locating the metal-to-metal seal close to said fluid flow pathadvantageously ensures that the fluid is transmitted from one pipe toanother with penetration into the components of the seal assembly 100.

In the described embodiment, a portion of the side wall 146 extends awayfrom the opening 112 of the connector body 102, at an angle ofsubstantially 4° with respect to the central longitudinal axis. In thedescribed embodiment, the tapered portion of the side wall extendsbetween the opening 112 of the connector body 102 and pointsubstantially at a mid-point of the connector body 102. In alternateembodiments, the tapered portion of the side wall may extend a greateror lesser distance into the connector body 102, in a direction away fromthe opening 112. Such a configuration has been found to advantageouslyallow a metal-to-metal seal to be created between the free end 114 of apipe 106 and the side wall 146 of the bore 144 of the connector body102, without unduly limiting the volume of the bore 144 available forthe transmission of a fluid through the connector body 102. Inalternative embodiments, the side wall 146 may taper at any other angleof less than 10° with respect to the central longitudinal axis. Infurther alternative embodiment, the side wall 146 may taper at an angleof greater than 10° with respect to the central longitudinal axis.

The first and second ends 108, 110 of the connector body 102 each have aradially extending end face 111. Each of said end faces 111 has a firstrecess 150, configured to receive the collar 138 at the first end 126 ofthe first ring 116, when the second ring 118 is moved, in contact withthe first ring 116, in the direction towards the connector body 102. Asthe first ring 116 is moved towards the connector body 102, the firstend 126 of the first ring 116 is received within the first recess 150until a second radial stop surface 152, provided at the first end 126 ofthe first ring 116, abuts a third radial stop surface 154 which definesa base wall of the recess 150.

The first end 126 of the first ring 116 is configured to nest within thefirst recess 150 when the second radial stop surface 152 is in abutmentwith the third radial stop surface 154. As can be seen in theillustrated embodiment, the collar 138 may have a tapered outer surfaceconfigured to cooperate with a side wall of the first recess, to assistthe passage of the first end of the first ring into the first recess.

In the described embodiment, the recess 150 has an opening 149, theradial width of which is substantially 30% of the radial width of theconnector body 102. In alternative embodiments, the opening 149 may havea width of another dimension less than 50% of the radial width of theconnector body.

Providing the first recess 150 with said dimensions allows for theradial width of the connector body 102 to be maximised as far aspossible. This means that in forming the recess, material is not removedfrom the connector body 102 to an extent that may compromise thestructural or mechanical integrity of the connector body 102.

In the described embodiment, the first recess 150 extends continuouslyaround the circumference of an end face 111 at each of the first andsecond ends 108, 110 of the connector body 102. In alternativeembodiments, the first recess 150 may comprise a plurality of individualrecesses, arranged evenly or unevenly around the circumference of theend face 111 at each of the first and second ends 108, 110 of theconnector body 102.

As illustrated in FIGS. 2 and 3 , the connector body 102 is configuredsuch that the first recess 150 is located adjacent the outer surface ofthe pipe 106 when said pipe 106 is inserted into the open end 112 of theconnector body 102. As shown in FIG. 3 , when the mechanical interlockarrangement 104 is in the secured condition this allows theinterconnection between the first end 126 of the first ring 116 and thefirst recess 150 to be located adjacent the outer surface of the pipe106. Such a configuration ensures that the concentricity of the firstring 116, the second ring 118, the connector body 102 and each insertedpipe 106 is maintained. This is particularly important for maintainingthe integrity of the metal-to-metal seal once the seal assembly isoperational and conveying fluid between two pipes.

When the mechanical interlock arrangement 104 is secured with respect tothe connector body 102 (i.e. in the secured condition), theinterconnection between the first ring 116 of the adaptor 115 and theconnector body 102 may act as a pivot point when externally actingforces, such as bending moments, act on a connected pipe 106. It hasbeen found that by minimising the radial distance of this point from thepipe 106 can greatly reduce the impact of said external forces on theintegrity of the metal-to-metal seal between the free end of the pipeand the connector body. As a result, the likelihood of fluid leakage isgreatly reduced.

In the described embodiment, the seal assembly 100 further includes alocating arrangement 156 for ensuring the alignment of the adaptor 115with respect to the connector body 102, as the second ring 118 is movedin the direction towards the connector body 102. The locatingarrangement 156 includes an end face at the first and second ends 108,110 of the connector body 102 having a second recess 158, and an endface of at first end 134 of the second ring 118 having a plurality ofprojections 160 configured to be received within the recess 158 duringmovement of the second ring 118 in the direction towards the connectorbody 102.

The locating arrangement 156 further ensures that the concentricity ofthe first ring 116, the second ring 118, the connector body 102 and eachinserted pipe 106 is maintained by securing the position of the secondring 118 relative to the connector body 102 when the mechanicalinterlock arrangement is in the secured condition, as illustrated inFIG. 3 . Advantageously, this further ensures that reliablemetal-to-metal seal is maintained between the connector body 102 andeach inserted pipe 106 even when each pipe 106 may be subject toexternally acting forces, such as a bending moment.

In the described embodiment, the second recess 158 extends continuouslyaround the circumference of the end face 111 of each of the first andsecond ends 108, 110 of the connector body 102. The second recess 158 isconcentric with the first recess 150. In alternative embodiments, thesecond recess 158 may comprise a plurality of individual recesses,arranged evenly or unevenly around the circumference of the end face 111of each of the first and second ends 108, 110 of the connector body 102.

In the described embodiment, the projections 160 of the locatingarrangement 156 comprise a series of castellations. The projections 160extend laterally from the first end 134 of the second ring 118, and aredistributed at evenly spaced intervals around the first end 134 of thesecond ring 118. Advantageously, distributing the projections 160 atregular intervals around the circumference of the first end 134 of thesecond ring 118 ensures that should an external force, such as a bendingmoment, act on a pipe 106 inserted into the connector body 102, the loadis more evenly distributed around the interface between the second ring118 and the connector body 102. The even distribution of said forcetherefore greatly reduces the likelihood that the concentricity of thefirst ring 116, the second ring 118, the connector body 102 and eachinserted pipe 106 relative to one another will be lost, and as such,greatly reduces any negative impact on the integrity of themetal-to-metal seal between the connector body 102 and the free end ofeach pipe 114.

In the described embodiment the castellations 160 are arcuate. It hasbeen found that by providing arcuate castellations, such a configurationfurther distributes said externally acting force more evenly across eachprojection 160. Advantageously, the likelihood that any one projection160 may fail and break away from the second ring 118 under the action ofsuch a force, is greatly reduced.

In alternative embodiments the projections 160 of the locatingarrangement 156 may be non-arcuate castellations, and in addition, maynot be castellated. Furthermore, the projections may instead be a singlecontinuous projection extending continuously around the circumference ofthe end face 111 of each of the first and second ends 108, 110 of theconnector body 102.

Referring again to FIG. 3 , the mechanical interlock arrangement 104further includes a fastening arrangement 162. The fastening arrangement162 is configured such that fastening of the fastening arrangement 162acts to pull the connector body 102 in the direction of the adaptor 115(i.e. towards the secured position), and at the same time, move thesecond ring 118 in the direction towards the connector body 102. Whenthe second ring 118 is moved in the direction of the connector body 102whilst being in contact with the first ring 116, the pipe 106 is driveninto the connector body 102 allowing the free end 114 of the pipe 106 tobe driven into contact with the side wall 146 of the bore 144. Morespecifically, the outer surface 148 of the free end 114 of the pipe 106is driven into contact with the side wall 146 of the bore 144. As aresult, a metal-to-metal seal is created between the free end 114 of thepipe 106 and the connector body 102.

The fastening arrangement 162 includes the second ring 118 having aplurality of fasteners 164, and the connector body 102 having aplurality of fastening points 166 configured to receive said fasteners164. By providing the second ring 118 with a plurality of fasteners 164,and the connector body 102 with a plurality of fastening points 166configured to receive said fasteners 164, the second ring 118 can beadvantageously quickly and easily attached to the connector body 102upon the mechanical interlock arrangement 104 having been moved fully inthe direction of the connector body 102, such that a metal-to-metal sealexists between the connector body 102 and the free end 114 of aninserted pipe 106. In addition, the second ring 118 can be quickly andeasily detached from the connector body 102 by virtue of said attachmentbeing releasable, should an operator wish to remove the seal assembly100.

In the described embodiment the fasteners 164 are threaded bolts. Thebolts 164 are arranged such that they penetrate apertures 168 formed inthe second ring 118, said apertures extending between the first andsecond ends 134, 136 of the second ring 118. The bolts 164 are arrangedsuch that the head portion is located adjacent the second end 136 of thesecond ring, with the threaded shaft penetrating the aperture 168between the second 136 and first ends 134. In the described embodiment,the fastening points 166 are threaded recesses having a threadconfigured to correspond to that of the fasteners 164, and are providedin the first and second ends 108, 110 of the connector body 102. Morespecifically, the threaded recesses 166 are located in a base wall 170of the second recess 158. In the described embodiment, the fasteningpoints 166 are arranged at evenly spaced intervals around the base wall170 of the second recess 158, at positions that correspond to those ofthe apertures 168, and as such the fasteners 164, which are arranged atevenly spaced intervals around the circumference of the second ring 118.

Advantageously, distributing the fasteners 164 at regular intervalsaround the circumference of the second ring 118 ensures that should anexternal force, such as a bending moment, act on a pipe 106 insertedinto the connector body 102, the load is more evenly distributed aroundthe interface between the second ring 118 and the connector body 102.The even distribution of said force therefore greatly reduces thelikelihood that the second ring 118 may become detached from theconnector body 102, or that the concentricity of the first ring 116, thesecond ring 118, the connector body 102 and each inserted pipe 106relative to one another will be detrimentally affected. Such aconfiguration therefore greatly reduces any negative impact of such anexternal force on the integrity of the metal-to-metal seal between theconnector body 102 and the free end 114 of each pipe 106.

Upon complete fastening of the fastening arrangement 162, the secondring 118 is releasably attached to the connector body 102, with themechanical interlock arrangement 104 fully secured in the securedcondition. Advantageously, the metal-to-metal seal between the free end114 of the pipe 106 and the connector body 102 can be securely andreliably maintained once created, with relative movement between eachconnected pipe 106 and the connector body 102 minimised.

As illustrated best by FIG. 1 , each aperture 168, and as such fastener164, is located such that the position alternates with the position ofeach projection 160 of the locating arrangement 156. Advantageously,distributing the fasteners 164 and projections 160 at regular,alternating intervals around the circumference of the second ring 118maximises the stability of the interface between the second ring 118 andthe connector body 102, and optimises the distribution of load should anexternal force, such as a bending moment, act on a pipe 106 insertedinto the connector body 102.

Throughout the description and claims of this specification, the words“comprise” and “contain” and variations of the word, for example“comprising” and “comprises”, means “including, but not limited to”, andit is not intended to (and does not) exclude other moieties, components,integers or steps. Throughout the description and claims of thisspecification, the singular encompasses the plural unless the contextotherwise requires. In particular, where the indefinite article is used,the specification is to be understood as contemplating plurality as wellas singularity, unless the context requires otherwise.

Features, integers, characteristics or compounds described inconjunction with a particular aspect, embodiment or example of theinvention are to be understood as be applicable to any other aspect,embodiment or example described herein unless incompatible therewith.

The invention claimed is:
 1. A seal assembly, comprising: a connectorbody with an open end leading to an annular seal surface, configured forcontact with a free end of a pipe received in the open end, wherein theconnector body has a longitudinal axis, and the annular seal surfaceextends at an angle to, and tapers along, the longitudinal axis; anadaptor for securing at the free end of the pipe; and a mechanicalinterlock arrangement configured for coupling the adapter with theconnector body, and driving the adaptor in the direction of theconnector body, when the adaptor is secured at the free end of a pipe,for driving the free end of the pipe substantially along thelongitudinal axis and into sealing contact with the annular sealsurface; optionally, wherein the annular seal surface is a metal sealsurface.
 2. A seal assembly according to claim 1, wherein the mechanicalinterlock arrangement is configured for preventing or limiting axialmovement of the pipe relative to the connector body, when the adaptor issecured to an outer surface of the pipe and when the free end of thepipe is in sealing contact with the annular seal surface.
 3. A sealassembly according to claim 1, wherein the adaptor comprises a firstring, configured to be mounted around a circumference of the free end ofa pipe, and a second ring configured to cooperate with the first ring inorder to drive the first ring into engagement with an outer surface ofthe pipe.
 4. A seal assembly according to claim 3, wherein the firstring has an angled outer surface defining a first taper, and the secondring has an angled inner surface defining a second taper complimentaryto said first taper, and configured so that contact forces actingtherebetween increase upon axial movement of the second ring relative tothe first ring in the direction towards the connector body, for drivingthe first ring in a radial direction into contact with the outer surfaceof the pipe; optionally wherein the first ring has a first end, a secondend and a central longitudinal axis, and wherein the angled outersurface extends between the first and second ends at an angle of between5 and 15° with respect to the central longitudinal axis; optionally,wherein the angled outer surface extends at an angle of substantially 8°to the central longitudinal axis.
 5. A seal assembly according to claim3, wherein the first ring comprises a first radial stop surface,arranged for abutment by the second ring, to limit movement of thesecond ring in the direction towards the connector body.
 6. A sealassembly according to claim 3, wherein the connector body includes afirst recess, and wherein a first end of the first ring is configured tonest within said recess when the second ring is driven in the directionof the connector body; optionally, wherein the first end of the firstring comprises a tapered outer surface configured to cooperate with aside wall of the first recess, to assist the passage of the first end ofthe first ring into the first recess.
 7. A seal assembly according toclaim 6, wherein the first recess is configured to be arranged adjacentthe outer surface of the pipe, when said pipe is inserted into the openend of the connector body.
 8. A seal assembly according to claim 6,wherein an innermost wall of the first recess defines a radial stopsurface arranged to engage a second radial stop surface provided on thefirst end of the first ring, and wherein abutment of the second radialstop surface with the innermost wall of the first recess preventsfurther movement of the adaptor in the direction towards the connectorbody.
 9. A seal assembly according to claim 3, wherein an inner surfaceof the first ring is non-planar, and is configured to securely engagewith the outer surface of the pipe; optionally wherein the non-planarprofile of the inner surface of the first ring is configured to engagethe outer surface of the pipe by virtue of an interference fit; and/oroptionally wherein the first ring includes a keying surface configuredfor purchase into the outer surface of the pipe; or optionally whereinthe inner surface of the first ring comprises a profile configured tocomplement a non-planar profile of the outer surface of the pipe.
 10. Aseal assembly according to claim 9, wherein the inner surface of thefirst ring comprises a plurality of projections, configured to bereceived in a series of recesses on the outer surface of a pipe;optionally, wherein the plurality of projections comprise teeth orbarbs.
 11. A seal assembly according to claim 1, wherein the sealassembly further comprises a locating arrangement for ensuring a desiredalignment of the mechanical interlock arrangement with the connectorbody, as the adaptor is moved in the direction towards the connectorbody.
 12. A seal assembly according to claim 11, wherein the locatingarrangement comprises an end face of the connector body having a secondrecess, and an end face of the adaptor having a projection configured tobe received within said recess during movement of the adaptor in thedirection towards the connector body.
 13. A seal assembly according toclaim 11, wherein the locating arrangement comprises an end face of theconnector body having a plurality of recesses, and an end face of theadaptor having a plurality of projections configured to be receivedwithin said recesses; optionally wherein the projections comprise aseries of castellations, wherein said castellations project at regularintervals around the circumference of the adaptor; optionally, whereinsaid castellations are of arcuate form.
 14. A seal assembly according toclaim 1, wherein the mechanical interlock arrangement comprises afastening arrangement for pulling the connector body in the direction ofthe mechanical interlock arrangement, in order to drive the free end ofthe pipe into sealing engagement with the annular seal surface.
 15. Aseal assembly according to claim 14, wherein the fastening arrangementcomprises the adaptor having a plurality of fasteners, and the connectorbody having a plurality of fastening points, and wherein the fasteningarrangement is configured to releasably attach the adaptor to theconnector body; optionally wherein the adaptor has a plurality ofapertures extending therethrough, and wherein the fasteners areconfigured to be inserted through said apertures in the directiontowards the connector body; and/or optionally wherein the fasteners arearranged at regular intervals around the circumference of the adaptor,and wherein the fastening points are located at regular intervals aroundthe end face of the connector body, and wherein the position of eachfastener is complementary to the position of each fastening point;and/or optionally wherein the fastening points comprise a plurality ofrecesses, configured to align with the fasteners and to releasablyattach to said fasteners during movement of the adaptor in the directiontowards the connector body.
 16. A seal assembly according to claim 1,wherein the connector body comprises a second open end leading to asecond annular seal surface, configured for cooperation with a free endof a respective pipe; wherein the seal assembly further comprises; asecond adaptor configured for securing at the free end of the respectivepipe; and a second mechanical interlock arrangement configured forcoupling the second adapter with the connector body, and driving saidsecond adaptor in the direction of the connector body, when the secondadapter is secured at the free end of the respective pipe; optionally,wherein the second annular seal surface extends at an angle to thelongitudinal axis; and/or optionally, wherein the second mechanicalinterlock arrangement is further configured for preventing or limitingaxial movement of the respective pipe relative to the connector body.17. A seal assembly, comprising: a connector body with an open endleading to an annular seal surface, configured for contact with a freeend of a pipe received in the open end, wherein the connector body has alongitudinal axis, and the annular seal surface extends at an angle to,and tapers along, the longitudinal axis; an adaptor for securing at thefree end of the pipe; and a mechanical interlock arrangement configuredfor coupling the adapter with the connector body, and driving theadaptor in the direction of the connector body, when the adaptor issecured at the free end of a pipe, for driving the free end of the pipesubstantially along the longitudinal axis and into sealing contact withthe annular seal surface, wherein the annular seal surface extends awayfrom the open end of the connector body at an angle of less than 10°with respect to the longitudinal axis.
 18. A seal assembly according toclaim 17, wherein the annular seal surface extends away from the openend of the connector body at an angle substantially 4° with respect tothe longitudinal axis.
 19. A method of creating a metal-to-metal sealbetween a free end of a pipe and a connector body, the method comprisingthe steps of: providing a connector body with an open end leading to ametal annular seal surface, the connector body having a longitudinalaxis, and the metal annular seal surface extending at an angle to thelongitudinal axis; securing an adapter at a free end of a pipe; couplingthe adapter with the connector body via a mechanical interlockarrangement; and driving the adapter in the direction of the connectorbody via the mechanical interlock arrangement, such that the free end ofthe pipe is driven into sealing engagement with the metal annular sealsurface, to provide a metal-to-metal seal between said free end of thepipe and said metal annular seal surface.